Tesco selling groceries at Gatwick airport wouldn't normally be much of a story, but in this case, the company says it's the "UK’s first interactive virtual grocery store". In other words, it enables people to buy things using their mobile phones and have them delivered to their homes.

It's not the world's first "interactive virtual grocery store", or even Tesco's first. Tesco notched up those achievements last year when it used a very similar system to sell groceries in subway/underground/tube stations and at bus stops in Seoul, South Korea. (See my story from June 2011: Virtual supermarket shopping with a smartphone.) It won marketing agency Cheil Worldwide the Grand Prix in Media at the international advertising festival in Cannes.

The main difference is that this time it's using interactive digital displays, says Tesco. However, it's also using standard bar codes rather than the Denso Wave QR codes used in South Korea.

Customers select products, from a virtual fridge using an app on their Apple or Android smartphone. Obviously, they have to download the app and register with Tesco before they can shop.

The idea is that people fill their virtual baskets when leaving the UK, using some of their (roughly) 70 minutes of downtime in the airport. They schedule the home delivery for when they return, presumably leaving an allowance for flight delays.

However, this is an experiment rather than a commitment. The virtual store will only be open during the busiest holiday period from 6 – 19 August, and Tesco says "staff will be on hand to help customers with the scanning and ordering process on their smartphones". In the short term, this will add to the running cost.

Tesco’s Internet Retailing Director, Ken Towle, said in a statement: "Our business in Korea is teaching us a lot about how customers and technology are transforming shopping. It gives us a unique window into the future and the chance to try out exciting new concepts."

It's also getting the company plenty of favourable publicity.

Of course, many people already shop using their mobile phones, and the ability to shop, pay, and schedule deliveries while waiting for a plane, bus or train is useful. Consumers can already do that using apps on their smartphones, so the "virtual fridge" looks like a bit of a gimmick.

However, it does prompt consumers to buy when they otherwise wouldn't, and the ability to shop by scanning bar codes may make the process slightly easier. That should mean more money for Tesco, which is the ultimate aim.